Keywords: *CONCRETE DAMAGED PLASTICITY *CONCRETE TENSION STIFFENING *CONCRETE COMPRESSION HARDENING *CONCRETE TENSION DAMAGE *CONCRETE COMPRESSION DAMAGE
Compressive stress vs. strain components and volumetric strain under biaxial-compressive loading
Kupfer et al. (1969)
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Overview of ABAQUS Version 6.3
Mechanical Behavior of Plain Concrete
三轴加载：
高压混凝土裂纹扩展被阻止。脆性的特性被柔性硬化的特性代替。 Under high confining pressure, crack propagation is prevented. The brittle behavior disappears and is replaced by ductility with work hardening.
Keywords: *CAP PLASTICITY and *CAP HARDENING
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Overview of ABAQUS Version 6.3
加强筋(钢) 在ABAQUS中的应用
加强筋(钢)在ABAQUS中的应用
define rebar in beam elements:
Isoparametric rebar in three-dimensional membrane/shell elements:
Reinhardt and Cornelissen (1984)
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Stress-deformation curve under cyclic loading (large compressive stress)
Reinhardt and Cornelissen (1984)
Overview of ABAQUS Version 6.3
高压 (equivalent pressure stress many times larger than uniaxial compression failure stress) 混凝土的压碎(crushing) 是主导行为
大荷载 (非弹性) 单调荷载、循环荷载都可以
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Overview of ABAQUS Version 6.3
混凝土损伤模型 (ABAQUS Version 6.3)
高压力混凝土的本构关系
Cap model
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Overview of ABAQUS Version 6.3
Smeared Cracking Model (ABAQUS/Standard)
用于描述 单调应变 在材料中表现出拉伸裂纹或者压缩时破碎的行为 压缩塑性应变由“塑性压缩屈服面”控制 裂纹出现在当应力达到 裂纹产生面“crack detection surface”时
cracks parallel to the direction of the greatest compressive stress.
Typical plot of compressive stress vs. axial, lateral, and volumetric strain
. Overview of ABAQUS Version 6.3
混凝土双轴强度包络图
Biaxial strength envelope of concrete
Kupfer et al. (1969)
Failure modes of biaxially loaded concrete
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Overview of ABAQUS Version 6.3
Mechanical Behavior of Plain Concrete
混凝土 钢筋混凝土
ABAQUS
内容提纲
介绍
无钢筋混凝土力学行为
ABAQUS中的混凝土本构模型 加强筋(钢)ABAQUS中的应用 应用实例
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Overview of ABAQUS Version 6.3
介绍
介绍
Motivation: 构造两种不同应力状态的混凝土模型，预测混凝土和钢 筋混凝土的力学行为
Mechanical Behavior of Plain Concrete 双轴加载：混凝土失效应力大于单轴状态时的失效强度
Under biaxial compressive loading, concrete strength is greater than the one observed in uniaxial tests.
Triaxial concrete behavior
Chen (1982)
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Overview of ABAQUS Version 6.3
Mechanical Behavior of Plain Concrete
循环加载力学行为
塑性和刚度的退化
反向加载刚度恢复 (单向)
Stress-deformation curve under cyclic loading (small compressive stress)
裂纹是影响材料行为的最关键因素，它将导致开裂以及开裂后的材料的各 向异性 Keywords: 例题
. Overview of ABAQUS Version 6.3
*CONCRETE, *TENSION STIFFENING, *SHEAR RETENTION, and *FAILURE RATIOS
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单轴拉伸
Mazars and Pijaudier-Cabot (1989)
Overview of ABAQUS Version 6.3
Mechanical Behavior of Plain Concrete
体积膨胀: Volume increase that results from the formation and growth of
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Overview of ABAQUS Version 6.3
Cap Model
此模型最初于黏土材料
在Drucker-Prager剪切失效模型加了一个“cap”
Cap的作用
约束模型的静水压力 当材料剪切屈服时帮助控制体积膨胀
这些特性使得“cap”模型适用于受到高压的混凝土
静水压力别单轴压缩强度大很多 这不包括任何表示拉伸裂纹（cracking）和压缩破碎(Crushing)的 行为 因此只适用于收到高压的混凝土.
Cracking Model (ABAQUS/Explicit)
ABAQUS/Explicit中脆性破裂模型 适用于拉伸裂纹控制材料行为的应用 压缩失效不重要 此模型考虑了由于裂纹引起的材料各向异性性质
材料压缩的行为假定为线弹性.
脆性断裂准则可以使得材料在拉伸应力过大时失效
Keywords: *BRITTLE CRACKING, *BRITTLE FAILURE, and *BRITTLE SHEAR
1：
低压混凝土 (静水压力小于三倍单轴单轴压缩失效应力) ，占主导地位的是混凝土开裂（cracking）的行为 大荷载 (塑性阶段) ，次生裂缝行为明显 单调荷载（可以包括小的反向加载，但是不能模拟循环 加载）
. Overview of ABAQUS Version 6.3
介绍
2：Modeling the behavior of unreinforced and reinforced concrete structures
Skew Rebar in three-dimensional shell/ membrane elements: Define rebar in axisymmetric shell/ membrane elements: Define a layer of uniformly spaced rebar in continuum elements (skew/ ISOPARAMETRIC)
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Overview of ABAQUS Version 6.3
Reinforcement
We summarize here some of the new functionality in ABAQUS Version 6.3 for modeling reinforcement of structural and continuum elements. A number of improvements have been made to simplify rebar definition and provide rebar visualization in ABAQUS/CAE. A new *REBAR LAYER option is introduced to define one or multiple layers of reinforcement in membrane, shell, or surface elements. This option must be used in conjunction with the *MEMBRANE SECTION, the *SHELL SECTION, or the *SURFACE SECTION option.
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Overview of ABAQUS Version 6.3
Concrete Damaged Plasticity (ABAQUS Version 6.3)
适用于混凝土的各种荷载分析 单调应变, 循环荷载, 动力载荷. 标量损伤模型 (各向同性) ， 包含拉伸开裂(cracking)和压缩破碎(crushing). 此模型可以模拟硬度退化机制以及反向加载刚度恢复的混凝土力学 特性